Insulation displacement connector (IDC) technology was originally developed in the telecommunications industry for making multiple connections. IDC technology has been applied in many applications. For example, IDC technology is used in butt connections and splicing of electrical wires. In a butt connection, two wires are electrically connected together. In splicing, a wire is electrically connected to a trunk line. The IDC permits the connections to be made without a separate insulation stripping step because the IDC cuts and displaces the wire insulation with a sharpened conductor contact. Insulation piercing technology differs from IDC technology in that instead of forcing the wire into a sharpened connector, a piercing pointed stake is forced through the insulation and into the conductor.
Conventionally, connections were made by stripping wires and crimping or soldering connections. Stripping wires and crimping or soldering connections is time consuming and problematic especially for work taking place in the field. To avoid stripping, crimping, or soldering connections, connections were made from one electrical device to the next using a pig-tail wire with a factory installed connector (pin) with an environmental seal. The factory installed connector may be mated to a connector on the next electrical device. When the connection is made, an environmental seal is established. In some cases, the pig-tail may be connected to a trunk wire, which is subsequently connected to the next device. The trunk wire may have factory installed mating connectors at specific locations in the wire. Although factory installed mating connectors provide convenient installation, the mating connectors add considerable cost and lack flexibility since wire lengths or positions between connectors on trunk wires are fixed. Furthermore, mating connectors have been shown to have lower reliability than IDC technology.
In a variant of the trunk wire with mating connectors, a flat profile trunk line may utilize a factory installed connector with insulation piercing barbs. The final connection to the trunk line is made by piercing rather than pin based factory installed connectors. The flat profile trunk line is typically proprietary. Using proprietary wires limits options and availability, and also suffers from most of the same cost concerns as the factory installed pig-tail and end connectors. Once the specific piercing connector has been used to pierce a trunk line, the insulation piercing connector can be removed and either the trunk wire replaced or another device connected to the trunk wire at that point using another piercing connector. However, the piercing connectors and trunk wires must be in the same proprietary family of products. Again, this restricts material selection and availability. Also, this piercing connector does not provide the option of a butt connection. If a section of trunk wire must be replaced, either the entire wire must be replaced or a separate butt splice must be performed and environmentally sealed to connect the new section of trunk line to the remaining trunk line.
Existing IDCs are inadequate for use in solar microinverter connection applications. IDC technology is commonly intended for single use and in applications where an environmental seal is required. For example, removing the IDC connector exposes the wire's conductor to the environment at the point where the insulation has been displaced. IDCs that have been used in power line applications have a seal, but if the IDC is removed and replaced by another IDC, the environmental seal is generally not preserved. This is especially problematic in the solar energy context because solar panels are typically located in outdoor areas that are susceptible to environmental conditions. For example, solar panels may be placed on the rooftops of residential homes or even high rises, both of which may endure high winds, precipitation, freezing temperatures, and freeze and thaw conditions.
Existing IDCs are designed for either wire to wire or printed circuit board (PCB) to wire applications. PCB to wire IDCs are not environmentally sealed. In the solar energy context, the trunk line and component parts are connected to the microinverter. The connection with the microinverter is an opportunity for sealant problems to occur due to the insulation or the IDC environment being breached. Furthermore, the mechanical nature of conventional IDCs makes a conventional IDC capable of either a butt connection or a splice connection, but not both in the same connector. Thus, in a situation where either a section of a trunk wire is damaged and needs to be replaced or the end of a trunk wire length and an additional length needs to be added, a combination of several separate environmentally sealed connections would have to be made. This has disadvantages of cost, time, and increased potential for leakage as many environmental seals would need to be maintained.